1. Field
The present disclosure relates to a resonator for a vehicle, and more particularly, to a resonator for a vehicle, in which a plurality of resonance chambers are formed between an outer pipe configuring an outward appearance and an inner pipe disposed inside the outer pipe to improve noise reduction performance of the resonator.
2. Description of the Related Art
Generally, an intake system of a vehicle includes an air cleaner, a turbo-charger, an inter-cooler, an air duct and an engine manifold, and an external air introduced into an internal combustion engine by the intake system is repeatedly expanded and shrunken to cause intake pulsation. The intake pulsation causes noise due to the change of air pressure, and particularly, greater noise is caused due to air resonance of a vehicle body or an indoor space of the vehicle.
In order to restrain the intake noise, a resonator for tuning the intake system into a specific frequency is installed at an intake hose which connects the air cleaner to the intake manifold.
As an example of existing resonators, Korean Patent Publication No 2006-0116275 discloses a resonator, which includes an outer pipe configuring an outward appearance and an inner pipe installed in the outer pipe to give an air passage. A resonance chamber for tuning air frequency to reduce noise is formed in a space between the outer pipe and the inner pipe, and a slit for guiding air to the resonance chamber is formed at the inner pipe. In other words, the air flowing into the inner pipe moves to the resonance chamber through the slit, and the air moving to the resonance chamber may experience frequency tuning, thereby performing noise reduction of the air.
However, this resonator has a limit in the number of resonance chambers, and thus the frequency tuning work for external air cannot be performed over a broad band. In other words, since the resonator has a limited number of resonance chambers, the degree of frequency tuning freedom is low, and thus the noise reduction for external air is not performed agreeably.
Korean Patent Publication No. 2009-0047083 discloses a resonator in which a first duct and a second duct with different sectional areas are disposed therein, and a length of a region where two ducts overlap with each other is adjusted to reduce noise of a specific frequency. However, in spite of this technique, the number of resonance chambers for noise reduction is still limited, and thus it is not easy to reduce noise of a broad band. In particular, a turning work at a high frequency band is not easy, and thus noise reduction efficiency for external air is low.